About

Karen Trapenberg Frick is the Director of the Institute of Urban & Regional Development and an Associate Professor of City & Regional Planning at UC Berkeley. She holds a PhD in City & Regional Planning from UC Berkeley, an MA in Urban and Regional Planning from UCLA, and a BA in Sociology from UCLA. Her teaching encompasses graduate and undergraduate classes in transportation policy and planning, global cities, planning history and theory, and dissertation research design. She was also the academic lead for CED's [IN]CITY summer program in sustainable city planning. Her research expertise includes sustainable transport and community-based planning, with a focus on major transportation infrastructure projects. Her current research investigates conservative, Tea Party, and property rights activists' perspectives on planning and how planners respond to these viewpoints. She has received recognition for her research, including a 'Best Paper of the Year' Award from the Journal of the American Planning Association. Her work has been published in prominent journals such as Urban Studies, Planning Theory and Practice, and the Journal of Planning Education and Research. Additionally, she co-curated and contributed to a collection of essays titled “Strengthening Planning’s Effectiveness in a Hyper-Polarized World.” Prior to her academic career, Karen worked as a transportation planner at the San Francisco Bay Area's Metropolitan Transportation Commission for nine years, where she contributed to programs including Transportation for Livable Communities, congestion pricing, and transport funding and policy. She has been recognized for her community partnership and advising efforts, receiving awards such as the 2016 Award for Outstanding Faculty Advising from UC Berkeley and the 2019 STEM Partner Award for her collaboration with Self e-STEM, a nonprofit providing STEM education and mentoring to underserved youth in the Bay Area.

Research topics

• Computer Science
• Demographic economics
• Economics
• Transport engineering
• Medicine
• Engineering
• Geography
• Computer Security
• Business
• Sociology
• Advertising
• Mathematics
• Statistics
• Data science
• Psychology

Selected publications

• How do Cyber-Risks Vary Across Smart City Technologies?

  Journal of Urban Technology · 2025-07-02 · 2 citations

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Accountability to God, We the People and Local Government Activism in Rural Shasta County, California

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access1st authorCorresponding
  PublisherDOI

• Early Pandemic Behaviors and the Role of Vaccines in Reversing Pandemic Mobility Trends: Evidence from a U.S. Panel

  Transportation Research Record Journal of the Transportation Research Board · 2024-06-07 · 2 citations

  article

  The COVID-19 pandemic disrupted travel behavior and resulted in the emergence of new mobility trends. In this paper, we study the degree to which vaccines played a role in reversing pandemic-induced travel behaviors and contributed to a “return to normal.” Using five waves of original U.S.-based survey data combined with passive smartphone tracking data collected in 2020 and 2021, we show that in the early phases of the pandemic, the behavioral response of people in the United States was heterogeneous: individuals with low levels of concern about being infected with COVID-19 engaged in riskier behaviors than those with higher levels of concern, such as traveling more, eschewing masks, attending large gatherings, and using public transportation. Vaccine availability in early 2021 played a significant role in reducing those concerns, which in turn was reflected in significantly increased mobility and travel frequency. We also found a strong positive association between getting vaccinated and the frequency of using public transportation. Telecommuting and working from home remained high after vaccine availability, but we found that the fraction of full-time employees that worked from home every day significantly dropped. This reduction in fully remote work was no different among vaccinated and unvaccinated people, which suggests that the decision to return to in-person work was not only driven by employees’ safety concerns and preferences, but was also a function of employers’ expectations and their decision to reopen their offices. We discuss the implications of our findings on understanding travel behavior during pandemic impact- and recovery periods.

  PublisherDOI

• ACSP Distinguished Educator, 2019: Elizabeth Deakin

  Journal of Planning Education and Research · 2023-06-02

  article1st authorCorresponding
  PublisherDOI

• Tracking the state and behavior of people in response to COVID-19 through the fusion of multiple longitudinal data streams

  Transportation · 2023 · 4 citations

  • Computer Science
  • Computer Science
  • Geography
  PublisherDOI

• Never Waste a Crisis: How COVID-19 Lockdowns and Message Sources Affect Household Emergency Preparedness

  Natural Hazards Review · 2022-04-23

  articleOpen accessSenior author

  Public institutions are facing natural and manmade hazards of increasing frequency and severity. While the costs of disasters can be greatly reduced when individuals prepare, successfully encouraging preparation is difficult for governments, given the low salience of such risks. We examine whether the increased salience of other types of risks can influence individual willingness to prepare for natural and manmade hazards, and whether message impact varies with recipients’ levels of trust in their source. We capitalize upon a rare policy experiment—the staged rollout of COVID-19 lockdowns in California—to assess if increases in the salience of the pandemic were associated with greater willingness to store water for earthquake-induced system outages. We find that experiences of a disaster in a different domain (public health) and higher levels of trust in message source both increase willingness to store water. This suggests that public agencies should encourage preparedness during actual emergencies, or “not let a crisis go to waste.”

  PublisherOA PDFDOI

• Tracking the State and Behavior of People in Response to COVID-1 19 Through the Fusion of Multiple Longitudinal Data Streams

  arXiv (Cornell University) · 2022-09-23 · 1 citations

  preprintOpen access

  The changing nature of the COVID-19 pandemic has highlighted the importance of comprehensively considering its impacts and considering changes over time. Most COVID-19 related research addresses narrowly focused research questions and is therefore limited in addressing the complexities created by the interrelated impacts of the pandemic. Such research generally makes use of only one of either 1) actively collected data such as surveys, or 2) passively collected data. While a few studies make use of both actively and passively collected data, only one other study collects it longitudinally. Here we describe a rich panel dataset of active and passive data from U.S. residents collected between August 2020 and July 2021. Active data includes a repeated survey measuring travel behavior, compliance with COVID-19 mandates, physical health, economic well-being, vaccination status, and other factors. Passively collected data consists of all locations visited by study participants, taken from smartphone GPS data. We also closely tracked COVID-19 policies across counties of residence throughout the study period. Such a dataset allows important research questions to be answered; for example, to determine the factors underlying the heterogeneous behavioral responses to COVID-19 restrictions imposed by local governments. Better information about such responses is critical to our ability to understand the societal and economic impacts of this and future pandemics. The development of this data infrastructure can also help researchers explore new frontiers in behavioral science. The article explains how this approach fills gaps in COVID-19 related data collection; describes the study design and data collection procedures; presents key demographic characteristics of study participants; and shows how fusing different data streams helps uncover behavioral insights.

  PublisherOA PDFDOI

• Public transit use in the United States in the era of COVID-19: Transit riders’ travel behavior in the COVID-19 impact and recovery period

  Transport Policy · 2021 · 218 citations

  • Business
  • Geography
  • Transport engineering

  COVID-19 has upended travel across the world, disrupting commute patterns, mode choices, and public transit systems. In the United States, changes to transit service and reductions in passenger volume due to COVID-19 are lasting longer than originally anticipated. In this paper we examine the impacts of the COVID-19 pandemic on individual travel behavior across the United States. We analyze mobility data from Janurary to December 2020 from a sample drawn from a nationwide smartphone-based panel curated by a private firm, Embee Mobile. We combine this with a survey that we administered to that sample in August 2020. Our analysis provides insight into travel patterns and the immediate impacts of the COVID-19 pandemic on transit riders. We investigate three questions. First, how do transit riders differ socio-demographically from non-riders? Second, how has the travel behavior of transit riders changed due to the pandemic in comparison to non-riders, controlling for other factors? And third, how has this travel behavior varied across different types of transit riders? The travel patterns of transit riders were more significantly disrupted by the pandemic than the travel of non-riders, as measured by the average weekly number of trips and distance traveled before and after the onset of the pandemic. This was calculated using GPS traces from panel member smartphones. Our survey of the panel revealed that of transit riders, 75% reported taking transit less since the pandemic, likely due to a combination of being affected by transit service changes, concerns about infection risk on transit, and trip reductions due to shelter-in-place rules. Less than 10 percent of transit riders in our sample reported that they were comfortable using transit despite COVID-19 infection risk, and were not affected by transit service reductions. Transit riders were also more likely to have changed their travel behavior in other ways, including reporting an increase in walking. However, lower-income transit riders were different from higher-income riders in that they had a significantly smaller reduction in the number of trips and distance traveled, suggesting that these lower-income households had less discretion over the amount of travel they carried out during the pandemic. These results have significant implications for understanding the way welfare has been affected for transportation-disadvantaged populations during the course of the pandemic, and insight into the recovery of U.S. transit systems. The evidence from this unique dataset helps us understand the future effects of the pandemic on transit riders in the United States, either in further recovery from the pandemic with the anticipated effects of mass vaccination, or in response to additional waves of COVID-19 and other pandemics.

  PublisherDOI

• Replication Data for: Never Waste a Crisis - How COVID-19 Lockdowns and Message Sources Affect Household Emergency Preparedness

  Harvard Dataverse · 2021-11-02

  datasetOpen accessSenior author

  This directory includes the replication files for "Never Waste a Crisis: How COVID-19 Lockdowns and Message Sources Affect Household Emergency Preparedness". The directory holds the anonymized survey data, auxiliary input data files, and R script necessary to replicate the main and supplementary tables and figures in the paper.

  PublisherDOI

• Travel of TOD Residents in the San Francisco Bay Area: Examining the Impact of Affordable Housing

  eScholarship (California Digital Library) · 2020-06-30

  articleOpen access
  Publisher

Frequent coauthors

• Elizabeth Deakin

  University of California, Berkeley

  21 shared

• Alexander Skabardonis

  Institute of Transportation Engineers

  9 shared

• Phyllis Orrick

  9 shared

• Robert Cervero

  University Transportation Research Center

  7 shared

• Daniel G. Chatman

  6 shared

• Greg Marsden

  6 shared

• Anthony May

  6 shared

• Raja Sengupta

  KIIT University

  6 shared

Awards & honors

• 2016 Award for Outstanding Faculty Advising from UC Berkeley…
• 2019 STEM Partner Award with the College of Environmental De…